Wraparound carton blank with split margins and tension tear strips



May 21, 1968 E. J. GRASER 3,384,291

WRAPAROUND CARTON BLANK WITH SPLIT MARGINS AND TENSION TEAR STRIPS Filed Dec. 13. 1966 2 Sheets-Sheet 1 f: 133;? H l INVENTOR' EARL J 6/3455? A 7' TORNE Y May 21, 1968 E. J. GRASER 3,384,291

WRAPAROUND CARTON BLANK WITH SPLIT MARGINS AND TENSION TEAR STRIPS Filed Dec. 15. 1966 2 Sheets-Sheet 2 INVENTOR. EARL J GRASE/P [IG4 a z g ATTORNEY United States Patent 3,384,291 WRAPAROUND CARTON BLANK WITH SPLIT MARGINS AND TENSION TEAR STRiPS Earl J. Graser, Monroe, La., assignor, by mesne assignments, to Glinkraft, Inc., West Monroe, La., :1 corporation of Delaware Filed Dec. 13, 1966, Ser. No. 601,518 Claims. (Cl. 229-40) ABSTRACT OF THE DISCLOSURE A blank for a wraparound article carrier which is provided with narrow tension or tear strips adjacent blank openings operative to effect limited and controlled localized tearing to generate additional access for distinct portions of a wrapped article in the event the blank is drawn about the articles packaged with excessive tension.

The present invention relates to wraparound article carriers and in particular to an improved blank structure for said carriers.

Machiney for folding and locking a blank including a cross section of an assembled package is shown and described in US. Patent 3,220,155, issued Nov. 30, 1965 to Earle C. Sherman.

Reference to the above cited patent is made in order to apprise one of the background or setting from which the present invention arose.

A particular feature of the invention is the provision of a wraparound blank which is provided with small tension or tear strips operative to relieve hoop stress in the wraparound blank after it is combined with articles to form a unitary package; said tear strips being operative to prevent excessive, uncontrolled or unlimited tearing of the blank.

An additional feature of the invention is the provision of a novel blank structure in the region of the carrier lock effective to eliminate undesirable friction arising from the natural tendency of the blank to resist bending. In effect, this feature provides a plurality of individual or separately identifiable lock sections in contrast to prior art blanks which have one continuous lock section.

A fiat blank convertible into a wraparound article carrier and embracing certain principles of the present invention may comprise hinged, opposed end margins defining first and second margins, said first margin being cut and scored to define a plurality of locking tabs operable to engage and make a locking connection with a locking bar formed on the second margin, said first margin being separated or divided into at least two sections so that a first section of said first margin can be manipulated relative to said locking bar separately and individually from the subsequent and similar manipulation of a second section whereby a substantial portion of the resistance to bending of said first margin is overcome.

A fiat blank for an article carrier embracing certain other principles of the present invention may comprise a plurality of openings formed in the blank, each opening having a periphery and each opening being operative to permit a portion of an article to project through a mating opening, at least one through-cut spaced from and generally following the contour of a portion of the periphery of each said opening, a portion of the blank between the periphery of each opening and the mating throughout defining a tear strip of limited width operative to provide limited or controlled additional access for each said article in the event the hoop stress (tension) of the blank drawn and locked about the articles is excessive.

Other features and advantages of the present invention will become more apparent from an examination of "ice the succeeding specification when read in conjunction with the appended drawings, in which:

FIG. 1 is a plan view of a wraparound blank embracing the principles of the invention;

FIG. 2 is a representation of a portion of the blank of FIG. 1 modified to show prior art structure;

FIG. 3 is a perspective view of the lower portion of a completed package utilizing a blank of the present invention;

FIG. 4 is an enlargement of a portion of FIG. 3 showing operation of a tear strip;

FIG. 5 is a perspective view showing an end margin of prior art structure (see FIG. 2) during the course of fabrication; and

FIG. 6 is a view similar to FIG. 5 showing the improvement of the present invention at a similar point during the course of fabrication.

Referring now in detail to the drawings, the reference numeral 10 designates a blank for a Wraparound article carrier of the type useful in the apparatus and convertible into the package shown and described in said U.S. Patent 3,220,155.

The blank 10 includes top wall 11, side walls 12 and 13, a bottom wall and hinged opposed end margins defining a first margin (outer margin in FIG. 3) indicated generally by the reference numeral 14 and a second end margin inner margin in FIG. 3) indicated generally by the reference numeral 16.

Note that first end margin 14 is divided into three sections 17, 18 and 19 by through-cuts 21 and 22. Sections 17, 18 and 19 hinged to first end margin 14 at score line 23 are individually rotatable about score line 23 to thrust locking tabs 24, 26 and 27 to the position shown on the right side of FIG. 6.

Opposite end margin 16 is formed with a locking bar 28 which cooperates with locking tabs 24, 26 and 27 as described in the Patent 3,220,155.

Blank 10 is further formed with a plurality of openings 2929 and 31-31, each providing limited access for the reception of a portion of mating articles D as is most apparent in FIG. 3.

Note further that a portion of the periphery 32 of each opening 29 and 31 is circumscribed by a spaced through-cut identified by the reference numeral 33.

The through-cuts 33 in conjunction with the portion of the periphery of opening 29 (and/ or 31) are contoured to define a tear strip or tension strip of limited width identified by the reference numeral 34.

The tear strips 34 are operable to tear or separate selectively and in controlled fashion, as shown in FIG. 4, to relieve tension or hoop stress developed in the carton when it is drawn and locked snugly about a plurality of articles to form a package.

Due to variations in bottle diameter or other structural variations in the article packaged, it is entirely possible that only one tem strip 34 separates relieving localized tension while others remain intact.

It is to be noted that the tear strip 34 is effective to minimize and control progress of carton tearing in that the spacing, location and width of the tear strip is selected to relieve local tension While blocking progress of a tear which would ultimately lead to possible destruction of the package.

Referring now to the end margin 14 as shown in FIG. 1 and to corresponding prior art end margin of FIG. 2, note that the relatively long margin of FIG. 2 has been divided into a plurality of sections 17, 18 and 19 by through-cuts 21 and 22.

The effect and advantage of this improvement is most apparent in FIGS. 5 and 6 where the prior art margin 190 is shown during the course of a fabrication step involving 3 rotating an end margin such as the margin 190 about its hinge line 191.

Assuming that the blank of FIG. 5 is moving in the direction indicated by the arrow of FIG. 5 such that the hinge line 191 is sliding along fixed plate 192 when fixed plate 193 is encountered margin 190 is caused to rotate about its score line 191.

As is apparent in FIG. 5, the leading edge 194 of the prior art blank of FIG. 5 first encounters the bending stress while the trailing edge 196 is last to pass through the bending elements 192 and 193.

The natural tendency of the blank 100 to resist bending is such that the trailing edge 196 of blank 100- is virtually flat and coplanar, while the forward or leading edge has been formed to the point where margin 190 virtually approaches a 90 angle relative to side wall 130.

The result of this occurrence is that excessive friction occurs in the forming machinery causing the carton blank to distort and generally resist smooth progress through the machine.

Referring now to FIGS. 1 and 6, note that by the division of end margin 14 into a plurality of sections namely 17, 18 and 19, the natural tendency for the margin to resist bending about its hinge line 23 (and thus the frictional resistance) is reduced to the point Where the leading and trailing edges of sections 17, 18 and 19 form up with virtual uniformity from end to end.

correspondingly by the development of margin sections such as sections 17 through 19, the work required to snap out locking tabs 24, 26 and 27 is substantially reduced because these tabs are actuated individually and sequentially by the individual rotation of the mating section 17, 18 or 19 as the case may be.

Referring now to FIG. 3, note that the carton lock indicated by the reference letter L is completed with the first end margin 14 overlapping or overlying the second end margin 16. For convenience in subsequently claiming the invention, the first end margin 14 may be referred to as the outer margin, while the second end margin 16 is referred to as the inner margin.

The through-cuts 21 and 22 effectively create three locking sections labeled A, B and C. Locking bar 28 cooperates with locking tabs 24, 26 and 27 while hinge flaps 36, 37 and 38 hinged to inner margin 16 cooperate with and are partially inserted into slits 3939.

The significant point being that the first and second end margins (outer and inner margins) operate by virtue of through slits 21 and 22 .to generate three lock sections A, B and C where prior to the present invention these mem bers generated a single lock section.

It is anticipated that a wide number of modifications may be devised in the blank of the present invention without departing from the spirit and scope of the princi ples thereof.

What is claimed is:

1. In a blank for a wraparound article carrier operative to encircle a plurality of articles tightly to form 11 package, the improvement comprising: at least one opening formed in the blank, said opening having a periphery and said opening being operative to receive a portion of an article encircled, at least one through-cut of predetermined length spaced from and positioned adjacent a portion of the periphery of said opening in a region of said opening which is susceptible of tearing, a portion of the blank between the periphery of the opening and its adjacent through-cut defining a tear strip of limited width, said tear strip being operable to tear or separate across its width to provide additional access for said portion of said article when a localized stress develops in said blank in the region of said portion of said article.

2. The blank of claim 1 in which said through-cut and said periphery are arcuate and define generally parallel lines.

3. In a blank for a wraparound article carrier operative to encircle a plurality of articles tightly to form a package, the improvement comprising: at least one opening formed in the blank, said opening being operative to receive a portion of an article encircled, at least one through-cut spaced in its entirety from said opening, said through-cut and said opening defining a tear strip, said tear strip being operative to control and to minimize tearing of said blank.

4. The blank of claim 3 in which said tear strip defines a narrow strip partially circumscribing said opening.

5. The blank of claim 3 in which a plurality of openings are formed in the blank, each opening being operative to receive a portion of a mating article and each opening being provided with at least one tear strip and each tear strip defining a relatively narrow, arcuate band partially circumscribing its mating opening.

References Cited UNITED STATES PATENTS 8/1966 Weiss 229-40 9/1966 Baker 2294() 

